What kind of toilet supply hookup is this?

I'm replacing an old water guzzler toilet from the 50's and ran into a water connection that I haven't seen before. It has a normal 3/8 supply tube with a plastic nut on the tank, but the bottom looks like it's either soldered or screwed into the floor. It's round and there is no compression nut like I'm used to. You can see some plier marks where someone had a wrench on it.

I attached a few pics. One is a connector I found online, which looks close. But it was for faucets and not toilets, so I'm not sure.

The plan is to replace this and add a shutoff valve at the same time. Since I have to turn off all the water in the house before doing this, I just want to make sure I know what I'm up against.

I am not sure what you have there either because I cannot tell the dimensions of the various parts. If that is a 3/8" o.d. tube, then that may be a compression nut with the actual adapter buried in the tile.

There's copper pipe under the tile, but I don't really have access. Best I can tell is that a bendable 1/2" copper pipe disappears into a stud and goes up through the mud floor. The house was built in the 50's, but the plastic nut at the tank leads me to believe this work is newer. The toilet is original.

I don't think the round part sticking out is copper. It seems harder like chrome or brass, and I don't see copper color from where the wrench was put on. It is a 3/8" OD tube coming going into the round fitting at the floor.

I might try to chisel out some of the grout around the fitting and go from there. I guess it wouldn't be bad if it were the top of a nut if I can get it out, but I never saw a round fitting like that.

Unfortunately there is no shutoff valve that controls just this, so the whole house has to be off while I figure it out.

Did they make 3/8" (iron pipe size) in chrome that was just a stub on the end without any threads? Either that, or maybe it was a normal chrome 3/8 IP nipple that someone cut? The OD of that round piece is very close to the OD of the 3/8IP nipple that's in the adjacent bathroom.

Maybe they soldered the 3/8" OD supply tube to the inside of that 3/8" pipe? Would that fit? If so, I can sweat it off but what kind of connector would I replace it with so I can have a shutoff? Can I solder something around the outside of if I scrape off the chrome?

Depending on the ID of the pipe...cut it off 4" above the floor line with a tubing cutter and use a 1/2" or a 3/8" Comp X 3/8 Comp shutoff and a flexable supply line...it realy depends on the ID of the line...there are a few things you can do...

There's copper pipe under the tile, but I don't really have access. Best I can tell is that a bendable 1/2" copper pipe disappears into a stud and goes up through the mud floor. The house was built in the 50's, but the plastic nut at the tank leads me to believe this work is newer. The toilet is original.

Click to expand...

The fill valve is probably not original, and some replacements come with parts that will work with any supply tube, including rubber compression that works with any 3/8 supply tube that's squarely cut. Roundabout way of saying the supply pipe may be original, but the toilet end could be not as you envision it, but just a cut end. And the plastic nut could have been put on much more recently.

That chrome brass for toilet supply is 3/8" IP size. Potentially you could fit a R14 chrome stop on the pipe if the chrome is completely filed/scraped off to the bare brass.Then solder it on. The 1/2" fitting will fit the 3/8 brass tubing.

Personally, I would rather unscrew the entire chrome/brass nipple and install a shorter 3/8 nipple with a 3/8" IPx 3/8" compression valve, and the rest is easy.

The chrome pipe you see is 3/8" chromed iron pipe. I assumed the tube to the toilet was 3/8" OD, but it looks closer to 7/16". I also attached a close-up of what looks to be the riser tube soldered into the pipe coming out of the floor. The floor pipe doesn't look to be cut though. I don't know why there'd be an unthreaded end like that???

I went looking for a valve that I could put on the 7/16" tube (assuming that's the size) then I could avoid messing with the floor fitting. Am I right to look for a 7/16" compression? The closest straight valve I could fine was labeled: 1/2" Nom. Compr. x 7/16" & 1/2" Slip-Joint... I'm not exactly sure what "slip joint" means... I know about the slip-joint drain connections but not slip-joint on the supply.

If it was just tile and thinset I'd be quicker to chisel out the floor, but it's a 2" mud bed and the whole area is very solid.

Those pictures are much better, but we still have to do some guessing. My guess is that it is a 3/8" chrome pipe without a thread, and a piece of 7/16" tubing was soldered into it. If so there are NO valves which will work on the unthreaded pipe, so you would have to unscrew it from a fitting and install a new threaded on both ends nipple, then install the valve.